I have been asked by a site owner to implement facebook style notification for the logged in user of all comments made by others to the logged in users posts, content, or comments. Specifically I am looking for the ability to have a counter type icon in the header/banner section of the site that will provide a count of unread notifications. Along with this a mouse over dropdown list of the unread comments/responses linkable back to the actual node where the comment is located for responding.
I have researched many of the modules/methods to create this condition for/in Drupal 7 and am confused about how to proceed. Is there anyone who has done this before in Drupal 7? There appears to be modules for this in Drupal 6 but fewer for Drupal 7.
Also in conjunction with this and as a future condition of the site we will be adding the capability of forums to the site. What group of modules do in need to implement to get the notification tasks to work as described above as well as extend the functionality of advanced forums capability in the future?
Thank you for any direction.